Postoperative nausea and vomiting (PONV) is one of the most common complaints in the postoperative period. It causes significant distress to patients after surgery. Despite all the advances in the last decades, the incidence of PONV is still between 20-30% (Cohen et al. Anesth Analg 1994; 78:7-16, Watcha, Anesthesiology Clin. N Am 2002; 20:709-722). Many different factors are associated with PONV; such as a past history of PONV, female gender, gynecological surgery, long duration of surgery, volatile anesthetics, postoperative opioids (Lerman Br J Anaesth 1992; 69:40S-45S), history of non-smoking and motion sickness (Ashraf et al. Can J Anesth 2004; 51:326-341). PONV also causes an increase in health care cost by prolonging stay in hospital (Gold et al. JAMA1989; 262:3008-10). There are many pharmaceutical options that have been developed over the past decades to treat PONV such as ondansetron, metoclopramide, propofol, corticosteroids and anticholinergics. Universal prophylaxis against PONV is neither cost-effective nor necessary. The best cost effective approach to manage PONV is to predict beforehand which patients will have nausea and vomiting after the surgery and to prevent its occurrence. There are ways to predict PONV by developing risk scores based on the before mentioned risk factors (Bellville et al. Anesthesiology 1960: 186-193). But there is currently no effective way to anticipate PONV. Female gender has been associated with a higher incidence of PONV compared to male patients (Koivuranta et al Anaesthesia 1997; 52: 443-449, Apfel et al. Acta anaesthesiol scand 1998; 42: 495-501). Gynecological surgery is a good setting to analyze PONV because patients are exclusively female; thus a higher incidence of PONV. Nausea is dependent on inherent factors such as age, gender and race and psychological factors such as anxiety, expectation and anticipation (Stern Acta Biologica Hungarica. 2002; 53(4): 589-99). The autonomic nervous system is implicated in the physiology of nausea. Increases in sympathetic activity and decreases in parasympathetic activity occur during nausea with an increase in abnormal dysrhythmic gastric activity and an increase in plasma vasopressin (Gianaros et al Psychophysiology 2003; 40(1):39-44). This can be seen in motion sickness and chemotherapy-induced nausea. It has also been also noted that an increase in baseline parasympathetic activity seems to set the stage for the expression of nausea (Morrow Psychophysiology 2000; 37(3): 378-84). Knowing that the autonomic system is implicated in the physiology of nausea, anticholinergic medications like scopolamine, which blocks muscarinic cholinergic central nervous system emetic receptors in the cerebral cortex and pons, have been used to treat PONV successfully (Kranke et al. Anesth Analg 2002; 95:133-43).